The government is facing up to the hidden environmental threats stemming from construction of the 180 billion yuan (US$24 billion) Three Gorges Project, experts and officials said at a workshop yesterday.

Environmental damage caused by the largest hydroelectric river dam project in the world needed to be addressed to avert a disaster, participants said at the two-day forum debating the project, in Wuhan, capital of Hubei Province.

On the plus side the dam will prevent seasonal flooding on the lower reaches of the Yangtze River and electricity generated by hydropower will reduce carbon emissions, but the benefits will have an environmental cost, they said.

Forum members said the project had "adversely" affected the Three Gorges reservoir environment.

Problems mentioned included disruption of the ecosystem, more frequent natural disasters, severe erosion and landslides, land shortages and ecological degradation.

Tan Qiwei, vice-mayor of Chongqing, a sprawling metropolis near the reservoir, said the shoreline had collapsed in 91 places.

Frequent geological disasters have threatened the lives of residents around the reservoir area, Huang Xuebin, chief of the Headquarters for Prevention and Control of Geological Disasters in the Three Gorges Reservoir.

At the forum he described landslides in the reservoir that had produced waves as high as 50 m, crashing into the shoreline and causing damage.

Water discharged from the Three Gorges Dam has threatened the safety of protective embankments downstream, Hubei Vice-Governor Li Chunming said.

Both Tan and Li said water quality in the Yangtze tributaries had deteriorated and outbreaks of algae and aquatic weeds had become more common.

"We cannot profit from a fleeting economic boom at the cost of sacrificing the environment," Wang Xiaofeng, director of the office of the Three Gorges Project Committee of the State Council, said.

Wang added the government had paid a lot of attention to the consequences of construction of the Three Gorges Dam.

The government has invested heavily in programs designed to conserve the ecology of the Three Gorges area, including spending 12 billion yuan to prevent disasters such as landslides.

It has also closed or relocated 1,500 manufacturing ventures, constructed more than 70 sewage disposal and waste treatment plants and resettled about 70,000 people from disaster-prone areas.

The Three Gorges Project was launched in 1993, with a budget of 180 billion yuan. Located on the middle reaches of the Yangtze River, the project boasts a 185 m dam, completed in early 2006, and a five-tier ship lock. At least 1.2 million people have been resettled.

(China Daily September 28, 2007)